Popis: |
We examine the mechanisms of pulse propagation inside tissue to determine the spectral intervals wherein the pulse might propagate to an occlusion and reflect from its boundary. We derive analytical expression, showing that the depth of occlusion may be determined upon measuring the time during which the input temperature pulse travels to the inclusion, is reflected from it, and returns to the front of the skin surface. Additionally, we derive the speed of pulse propagation from diffusivity and material time constants. These quantities are calculated from the published tissue parameters; they could also be calibrated for specific classes of the biological samples. For breast tissue monitoring, we propose to use near IR laser pulses. |